This invention relates to vascular surgery and minimally invasive surgery.
May people suffer from varicose veins and skin ulcers which are caused by venous insufficiency. The condition usually afflicts older people, and is most evident in the lower legs, and is evident in may people as large bumpy veins showing through the skin, discolored skin around the ankles, and open sores on the inside of the ankle. The condition is painful and disabling.
Venous insufficiency is often caused by failure of the valves located in small communicating veins which connect large superficial veins such as the posterior arch vein or saphenous vein, with large deep veins such as the peroneal or tibial veins. The communicating veins have valves which look like duckbill valves or leaflet valves that act as check valves, allowing blood to flow from the superficial veins into the deep veins, but blocking flow in the reverse direction. Exercise and movement of the calf muscles around the communicating veins squeezes blood through the communicating veins. This mechanical pumping action, combined with the function of the valves, is responsible for returning blood flow to the heart. When the valves fail, venous blood in the superficial veins cannot be pumped into the deeper veins, resulting in blood pooling in the legs. The condition causes very poor circulation in the legs and can lead to the varicose veins and skin ulcers. Large varicose veins in the lower leg, skin ulcers just above the ankle bone on the inside of the calf, and discolored skin on the lower leg are common symptoms. Similar symptoms are seen in other areas of the body, particularly the thighs and arms, when perforating veins in those areas become incompetent.
Venous insufficiency is generally attributed to the failure of certain groups of perforating veins. There are about 150 perforating veins in the leg, but there are several major perforating veins which are important contributors to the problem of venous insufficiency. An important group of perforators is found high on the inside of the calf, over the calf muscle. Another important group of perforators is found low on the inside of the calf, just above the ankle and toward the back of the leg. Another set of perforators which is found on the lateral or outside of the leg run through the muscles on the outside of the calf.
An effective surgical treatment of this condition was developed by Linton circa 1938. In the Linton procedure, also referred to as the Medial subfascial approach, the calf is cut open along the Linton line, extending from just above the ankle bone (or medial malleolus) on the inside or medial side of the foot, up the inside of the calf almost to the knee. The incision is deep enough to cut the skin and fat, and also the deep fascia which is a filmy fibrous layer of tissue which covers the muscles of the calf. Upon peeling away the skin, fat, and fascia, some of the communicating veins can be seen, and these are cut and tied off.
Another effective surgical treatment, similar to the Linton procedure is called the stocking seam approach. In the procedure, an incision is made along the back of the calf (where a seam would appear in an old fashioned pair of panty hose). The skin, fat, and fascia are cut and pulled away from the muscles to expose some of the communicating veins, and sometimes the large calf muscles are pulled apart to expose more communicating veins. This procedure can effectively cure the problem of venous insufficiency, provided that the major incompetent perforating veins are severed. One of the problems encountered in this therapy is that failure to sever all of the hemodynamically significant incompetent perforating veins may result in recurrence of the varicose veins and blood pooling.
Another problem encountered with the above procedures is that they require invasive open surgery with significant skin incisions which is undesirable in any case, but is particularly undesirable in cases of venous insufficiency because the poor blood flow makes it harder for the incisions to heal. Because the operation is so radical, it is often put off until the symptoms are severe. The high morbidity associated with this procedure has made it relatively unpopular, with the majority of patients with venous insufficiency opting for nonsurgical palliative treatment called compression therapy. Compression therapy is uncomfortable, lifelong, and does not correct the underlying hemodynamic pathology of incompetent venous valves. Thus, a minimally invasive procedure which requires tiny incisions far away from the ulcerated skin is desirable.